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Showing papers by "Tom J. Mabry published in 1992"


Journal ArticleDOI
TL;DR: Chloroplast DNA restriction site variation was studied in 31 New World species ofIpomoea, representing a majority of the New World sections and series within the genus, and refinements of existing classification schemes are proposed.
Abstract: Chloroplast DNA restriction site variation was studied in 31 New World species ofIpomoea, representing a majority of the New World sections and series within the genus. Using 14 endonucleases, a total of 124 phylogenetically informative restriction sites was detected. Dollo parsimony, Wagner parsimony, and bootstrap methods were employed to construct phylogenetic trees and evaluate confidence intervals of monophyletic groups. With a few exceptions, groups circumscribed on the basis of morphological variation are in agreement with groupings based on restriction site variation. Relationships between subgeneric groupings, however, disagree substantially with those proposed in the past. Although conflicting hypotheses for some intersectional relationships are not presently resolvable, cpDNA restriction site analyses propose the following refinements of existing classification schemes.Ipomoea ser.Setosae is divided into distantly related groups, as is sect.Pharbitis. SeriesTyrianthinae, a proposed segregate of sect.Pharbitis, is associated with sect.Calonyction and the Tricolor complex (subg.Quamoclit).Ipomoea sect.Batatas is segregated from other herbaceous groups of the heterogeneous subg.Quamoclit sensu lato and aligned as a derivative ofI. setosa, subg.Eriospermum. To test for homology of key characters weighted in traditional schemes, morphological features were studied with respect to their distribution on lineages defined by restriction site data. Characters such as setose sepals, foliose-pubescent sepals, and erect growth habit, among others, are interpreted as having multiple origins, while 3-locular ovaries, 4-locular ovaries, and long-haired seeds have evolved only once.

38 citations


Journal ArticleDOI
TL;DR: Treatment of old-man-cactus suspension cultures with chitin elicits synthesis of an aurone phytoalexin, cephalocerone, and increased extractable activities of the phenylpropanoid pathway enzymes phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS) and chal cone isomerase ( CHI) accompanied the synthesis of cep Halocer one.

27 citations


Journal ArticleDOI
TL;DR: Ten flavonoids were isolated from Cassia italica, including the first report of tamarixetin 3-rutinoside-7-rhamnoside, which is believed to be a new type of flavonoid.

21 citations


Journal ArticleDOI
TL;DR: A method for the quantitative determination of the nineteen protein amino acids by gas chromatography is described in this article, where the amino acids were allowed to react with isobutyl chloroformate in a basic aqueous medium and the resulting N(O,S)-isobuthyloxycarbonyl (isoBOC) amino acids are extracted into an organic solvent after acidification.

20 citations


Journal ArticleDOI
TL;DR: Leaves and stems from endod (Phytolacca dodecandra L'Herit), known to produce the 29 kDa ribosome-inactivating protein (RIP) dodecandrin, were initiated into tissue culture and immuno-reactive proteins were detected in callus and in suspension cells.
Abstract: Leaves and stems from endod (Phytolacca dodecandra L'Herit), known to produce the 29 kDa ribosome-inactivating protein (RIP) dodecandrin, were initiated into tissue culture. Callus and suspension cultures were maintained on modified Murashige and Skoog medium plus 1.0 mg/l 2,4-dichlorophenoxyacetic acid. Six callus and two suspension cell lines were screened for dodecandrin production by western blots with affinitypurified antiserum. Antiribosomal activity of culture extracts was tested by in vitro translation assays. One suspension cell line was found to be free of immunoreactive proteins and a ribosome inhibitor. All other cell lines contain a ribosome inhibitor, although only two callus cell lines show detectable amounts of immunoreactive proteins at the same Mr as dodecandrin. Other immuno-reactive proteins were detected in callus (Mr 31000, 33000, 41000 and 43000) and in suspension cells (Mr 23000 and ∼43000), and may be ribosome inhibitors related to dodecandrin—either other RIPs or dodecandrin at various stages of processing.

13 citations


Journal ArticleDOI
TL;DR: Pallenis spinosa was investigated for its flavonoid content and two mono- and diglycosides of patuletin, a quercetin monoglycoside, and four methoxylated flavonols were reported.

8 citations